The invention belongs to lubricating compounds and their preparation methods. Common knowledge includes numerous lubricant compounds, which can be applied for initial treatment of friction units of cars and mechanisms as well as for treatment during their operation, to extend time between overhauls or during maintenance and repairs.
Common knowledge includes a number of technical solutions aimed to solve similar engineering problems on friction reduction in friction units of cars and mechanisms, e.g.:
“Compound for the protective and antifriction surfaces formation on moving metal parts” (patent GB499338A), according to which the compound for the protective and antifriction surfaces formation on moving metal parts consists of zinc oxide, cadmium oxide, lubricating oil and vermiculite.
“Magnesium-containing dispersions” (U.S. Pat. No. 4,229,309A), according to which the process of preparing stable liquid of magnesium oxide containing dispersion is, essentially, in heating of the composition and includes energy-independent process liquid, containing Mg(OH)2 and dispersant agents of Mg(OH)2 dehydration temperature, where as long as there is non-dehydrated water, the above energy-independent process liquid can be heated to the Mg(OH)2 dehydration temperature, and the above dispersant agents can retain magnesium compounds, generated by dehydration in stable suspension.
“Lubricating compound and method” (application WO9640849A1), according to which lubricating compound contains super-absorbing polymers combined with the material to reduce friction between moving surfaces.
Common knowledge also comprises plenty lubricating compounds, which contain oxides of metals and non-metals, which in their stable phase contain oxides of magnesium (MgO), silicon (SiO2), aluminium (Al2O3), calcium (CaO), iron (Fe2O3), contained in the chemical compound of serpentine or talc.
Furthermore, the prior technical solution includes “Surface grease for objects contacting with water forms and method of its preparation” (U.S. Pat. No. 5,409,622), according to which the lubricant for local application on the surface of recreational equipment, designed for contacting with various forms of water to reduce friction between the abovesaid surfaces and abovementioned forms of water, the lubricating compound contains homogeneous mixture with at least 50% dispersed hexagonal boron nitride powder, water and the binding agent, selected from the group, consisting of cellulose, bentonite, hectorite, colloidal oxides, alkaline silicate and aluminium oxide, abovementioned aluminium oxide, obtained from the group, which is water-based colloidal aluminium oxide, peptized aluminium oxide and aluminium salt water solution, which can be transformed into the aluminium oxide by heating to the temperature of approx. 500-900° C.; this homogeneous mixture has the form of a paste. According to this technical solution, the lubricant compound is for the local application on the surface of recreational equipment, designed for contacting with various forms of water to reduce friction between the abovementioned surfaces and abovementioned forms of water, the abovestated lubricant body in the product is manufactured as follows: formation of homogeneous mixture of dispersed hexagonal powder boron nitride powder, water and the binding agent selected from the group, consisting of cellulose, bentonite, colloidal oxides, alkaline silicates, hectorites and aluminium oxide; this aluminium oxide, obtained from the group, which is water-based colloidal aluminium oxide, peptized aluminium oxide and aluminium salt water solution, which can be transformed into aluminium oxide which may be transformed into the aluminium oxide by heating to the temperature of approx. 500-900° C., formation of the abovementioned homogeneous mixture in the stated body; and drying this generated body to dehydrate it fully, the above dry body, contains hexagonal boron nitride ranging from 36 to 95 wt. %.
However, the technical solution, proposed under U.S. Pat. No. 5,409,622, has some drawbacks. Heating of water base of the colloidal aluminium oxide, peptized aluminium oxide and aluminium salt water solution to the temperature of 500-900° C. leads to bound water removal and crystal lattice destruction only, which insures removal only of hydroscopic moisture and water part, which is weakly bound in the crystal lattice. At the same time, as described above, provided a decay product penetrates, i.e. the product obtained in the result of thermal treatment in the range of 500-900° C., into the operating environment, e.g. lubricating compound, obtained product, assists in achieving only partial technical result, in particular, “lubricants for the local application to the surfaces of recreational equipment, designed for contacting with various water forms to reduce friction between the abovementioned surfaces and water forms”.
Furthermore, it is common knowledge that compounds for friction pairs restoration, involving dehydration products of such hydrates, which in their stable form contain oxides, namely, MgO, SiO2, Al2O3, CaO, Fe2O3, K2 O, ONa2 (“Compound for the treatment of friction pairs and method of its preparation”, U.S. Pat. No. 6,423,669). However, it was found that such compounds, as rule; at the same time do not contain all the oxides of those proposed under the oxide list in this technical solution.
For instance, a prior technical solution includes “Material for restoration of friction lining coupling” (patent of French Republic No. FR 2891333 dated 30 Mar. 2007), according to which friction lining couplings, including the material for restoration, at least partially, are coated with organic and inorganic hybrid material.
The common knowledge includes a technical solution, “Method of coating formation on friction surfaces” (patent of Russian Federation No. 2057257), which includes mechanical activation of finely dispersed mixture of minerals with the binding agent, placement of the obtained compound between the friction surfaces and its further run-in. In order to provide the diffusive penetration of the obtained coating into the friction parts surface the compound contains the mixture of minerals with dispersion 0.01-1.0 μm. Mechanical activation of the compound from the mixture of minerals and the binding agent is carried out by aperiodic fluctuations; at the same time the compound, placed between friction surfaces, contains (wt. %): mixture of minerals—3,3; binding agent—96,7, ingredient content of the abovementioned compound is the following, (wt. %): SiO-30-40; MgO-20-35; Fe203-10-15; FeO-4-6; Al203-3-8; S-2-6; concomitant residual elements—5-30; therewith, run-in is carried out under the pressure of not less than 10 MPa and temperature in micro-volumes not less than least 300° C.
The common knowledge includes a technical solution, “Method of servovite film formation on friction surfaces” (patent of Russian Federation No. 2059121 dated 27 Apr. 1996), where in order to improve the quality of the servovite film, which is achieved by contacting the element of the treated friction pair of higher or equitable hardness, in friction pairs of varied hardness, activated mixture is placed between them; this activated mixture contains the following ingredients, weight: abrasive-like powder of natural serpentinite 0.5-40, sulphur 0.1-5, surfactant 1-40, organic binding agent—the rest; at the same time, the treated pair element is magnetized and connected to the negative pole of the direct current source, while the technological part is connected to the positive pole. Both parts are run-in till the servovite film formation, after that the technological part is replaced with a pair element and is run-in in the same mixture.
However, the technical solution proposed under patent of Russian Federation No. 2059121 dated 27 Apr. 1996 has a number of substantial drawbacks. The main ingredient of the proposed compound is natural serpentinite of the Pechenga deposit, made in the following way. First, this natural serpentinite was dispersed to 500 μm and finer, then it was separated through the metal screen at the angle of 7° to the horizontal plane with the frequency of 50 Hz and fluctuation range of 2.5 mm at the angle of 30° to the horizontal plane with and with the mesh of 200 μm, ensuring clarification and particle size of up to 40 μm. After that it was redispersed to the size of up to 5 μm, separated with a permanent magnet, which contributed to clarification increase and grinding to 2 μm.
As it is evident from the description of the preparation method of the main ingredient—serpentinite, the nanostructure production process includes mechanical and magnetic impact on the natural mineral, which according to the Authors of this technical solution leads to the possibility of achieving the size of the nanostructure from 5 to 2 μm (5,000-2,000 n.m.). The Authors of this technical solution do not use interdependent temperature and time hold of the natural mineral, which does not allow to obtain the size of the nanostructure below 2,000 n.m. and what is more, it does not allow to achieve irreversible phase of the grain structure, which, eventually, leads to the fact that being promoted by natural characteristics of crystal lattice and by entering into the medium, e.g.—lubricant, due to the reverse water intake from the environment, serpentinite forms solid, indefinite\chaotic shaped masses, which act as abrasive materials under operational loads, and during friction surfaces operation this leads to the effect opposite to the restoration of friction surfaces.
The common knowledge includes a technical solution “Triboceramic compound” (US application No. 2010184585), according to which a triboceramic coating contains the oxides of—magnesium oxide (MgO), silicon oxide (SiO2), aluminium oxide (Al2O3), calcium oxide (CaO), ferrous oxide (Fe2O3), contained in the chemical composition of the serpentinite and talc, characterized by the fact that in order to expand the field of application, natural and/or synthesized non-heat-treated and/or dehydrated minerals—serpentine, talc, clinochlore, magnesite, quartz and hydro-aluminium oxide will be introduced into the triboceramic compound, ensuring the formation of the following triboceramic compound, wt. %: SiO2-46-54, MgO-26-32, Al2O3-2-5, Fe2O3-1.0-1.5, CaO-0.1-0.3, H2O-5 or less.
The common knowledge includes a technical solution “Additives for introduction to the fuel of mechanisms, additive application and treatment processes for mechanisms operating parts” (patent of Federal Republic of Germany DE102004058276 (WO2006058768), according to which “additives” are added to the lubricant or fuel of the internal combustion engine. Hereinafter, additives are applied to the lubricant and fuel, intended for the internal combustion engine. The technical solution proposed under patent DE102004058276 (WO 2006058768) includes iron magnesium hydroxide silicate. Furthermore, it contains such especially active components as silicate polymers and/or metal hydrosilicates (silicates), man-made or natural, consisting of one or several silicates of silicon-oxygen crystal lattice, in fibre, stripe, multilayer or tubular structures, in particular, reflected in formula ((MglFe)3K [Si2K O5k](OH)4Jn c k=1 up to 5, n=1 up to 10,000,000).
The Authors of the proposed technical solution believe that it is preferable to use serpentine according to chemical formula Mg6 [Si4 O10] (OH)8 and/or talc according to chemical formula Mg3[Si4O-io](OH)2. Magnesium sodium hydroxide silicate is used according to chemical formula Na2 Mg4 Si6 O-i[beta] (OH)2 by additional or alternative efficient designing of additives.
According to this technical solution, surfaces with the ceramic-metal coating (i.e. surfaces treated with the compound under this patent) are characterized by high corrosion resistance, notable through increased electric resistance of surfaces, high temperature stability (temperature of coating destruction is approx. 1,600° C.), microhardness, increased by 30 percent, as well as high pressure stability—up to 2,500 N/mm2 under contact compression strain.
However, the serpentine (Mg6[Si4O10](OH)8) and/or talc (Mg3[Si4O-io](OH)2) application leads to the opposite effect.
The closest to the proposed technical solution to its technical matter and proposed technical result, is the “Compound for the treatment of friction pairs and its preparation” (U.S. Pat. No. 6,423,669), according to which the compound for friction pairs treatment includes oxides of metals and non-metals. The compound contains the products of hydrates dehydration with the temperature of bound water removal and crystal lattice destruction in the range of 400-900° C. as abovementioned oxides, which in their stable phase contain oxides from the range MgO, SiO2, Al2O3, CaO, Fe2O3, K2O, Na2O.
The proposed technical solution refers to the composition of consistent lubricant compound, in particular, to the compound for friction pairs restoration, and can be applied in machine-building industry for friction units treatment. The proposed invention is in improving of the compound for friction pairs restoration. In this compound products of hydrates dehydration, which in stable phase contain oxides from the range MgO, SiO2, Al2O3, CaO, Fe2O3, K2O, ONa2 are applied. Formation of the stable compound condition is carried out by the structures of nanodisperse oxides, which minimize resistance to movement, friction pairs surface contact area and transfer in any form of the friction into the rolling friction, and therefore, friction pair surface is strengthened and friction coefficient is increased.
However, the proposed technical solution has some considerable drawbacks. Temperature conditions for bound water removal and crystal lattice destruction are in the range of 400-900° C., which ensures the removal of only hydroscopic moisture and water part, which is weakly bound in the crystal lattice, as well as the removal of chemically bound water; herewith, increase of heat setting and porosity, reduction of source material density and destruction of covalent links between layers are observed in the obtained decay products. Provided the decay product, i.e. the product obtained as a result of thermal treatment ranging within 400-900° C., enters into the operating environment, e.g. lubricating compound which normally consists of numerous “oil-based” components and various additives, there is the formation of compounds, which under the interaction with the operating environment (oil base+additives), due to the reverse water intake from the operating environment, form solid, indefinite-shape and/or chaotic shape formations, which under the operational loads in the units in or friction surfaces work as abrasive agent, i.e. have the opposite effect and increase the wear of the friction surface, create “scuffs,” “scratches” and reduce overhaul period of friction.
The basis of the proposed technical solution, is in the objective to obtain the lubricating compound, which, according to the invention, includes lubricant medium and natural mineral or natural mineral mix or synthesized hydrate dehydration product, where the dehydration product includes the oxides of MgO and/or SiO2 and/or Al2O3 and/or CaO and/or Fe2O3 and/or K2O and/or Na2O, obtained after bound water removal and crystal lattice at the temperature destruction from 400 to 900° C., Due to the fact that, in this compound dehydration product is obtained after bound water removal and crystal lattice destruction at up to 900° C., and achieves stable and/or irreversible phase at the temperature hold at 900-1,200° C., which ensures achieving nanostructure of the dehydration product within the range of 100-100,000 n.m.
Under the interaction of the proposed the lubricating compound with the surface materials, coating modification takes place, which may be described as the formation of ceramic-metal coating mostly consisting of metal carbides. As a result of experimental studies it was found that the lubricating compound provides the effect of mechanical interaction of nanoformations, obtained after decomposition of metal oxides, with the metal surface.
Technical effect, revealed under the lubricating compound application, is based on the fact that the original size of the revitalizant nanoformations is comparable with the size of surface defects (grainy texture, microroughness). This interaction leads to plastic flow of metal in nano-volumes and transition into the active nano-structured state of the surface layer. At the same time, intensive metal grain grinding occurs, the density of their boundaries is increased, the conditions for the diffusion of carbon into the surface (vertically) and into grains (horizontally) are improved.
Providing complex implementation of the proposed technical solution (compound and its preparation method), the Authors use the effect of bound water removal from some natural minerals, which, as it is well known can be constitutional, crystallization, zeolite and adsorption water. It is common knowledge that bound water is in the crystal lattice of the mineral as ions OH1−, less often H1+ and oxonium H3O1+. It is also known that it transits to the molecular state only under the mineral structure destruction, under heating, where separation of the bound water in each mineral is within the defined temperature range from 300° C. to 900° C.
Furthermore, the Authors of this technical solution, took into consideration the effect of hydrate moisture removal, i.e. the moisture, which is chemically bound with mineral admixtures and creates crystalline hydrates Al2O32SiO2-2H2O, Fe2O3-2SiO2-2H2O, CaSO4-2H2O, MgSO4-2H2O and others. This moisture escaped only under heating to the temperature of a least 600° C., volatile remnants of hydrate moisture are fully removed only under the temperature hold. Therefore, it was experimentally found that the temperature range of 400-900° C., without time hold is insufficient to remove volatile remnants of the hydrate moisture from dehydration products, which include e.g. the mixture of oxides: MgO and/or SiO2 and/or Al2O3. Consequently, the Authors found out that the removal of the volatile remnants of the hydrate moisture and obtaining irreversible state of the dehydration products, which contain the set of oxides MgO and/or SiO2 and/or Al2O3 and/or CaO and/or Fe2O3 and/or K2O and/or Na2O, is possible under higher temperatures, namely from 900 to 1,200° C.